The present embodiments relate to a mammography appliance with a stand, to which an appliance rack is attached. The mammography appliance includes a compressing unit with an object table and a compressing plate.
A mammography appliance is used to perform medical examinations of the soft tissue of the human breast with X-ray radiation. The medical examinations are used for the early identification of breast cancer. The breast is clamped between the object table and the compression plate, which can be moved toward the object table. An X-ray examination is then performed with the irradiation unit embodied as an X-ray tube. An X-ray detector is integrated in the object table. During the irradiation, soft X-ray radiation in the range below 50 kV, in particular below 30 kV is used.
Mammography appliances, such as the “Mammomat 1000”, “Mammomat 3000 Nova” and “Mammomat Novation,” have a similar structural design. As a representative example, the “Mammomat Novation” has a main body embodied as a stand and an appliance arm protruding from the stand at an angle at the free end of which a radiation source is arranged. The appliance arm is implemented as a sheet-metal structure and connected in a rotationally fixed manner to a horizontal rotary axis of the mammography appliance so that the radiation source can be swiveled 360° about an isocenter. An object table is mounted on the appliance arm by a rotary joint and can be swiveled 360° about the isocenter.
The protruding angled appliance arm, to which the irradiation unit and the compression unit are attached, exerts high mechanical leverage forces, which require a complex mechanical design. The appliance arm also performs the rotary or swivel movements required for the different types of examination. For example, the mammography device is usually used for screening examinations, in which the irradiation unit is located in a 0° position. The irradiation unit and the object table are arranged opposite each other in the longitudinal direction. The mammography appliance is designed for a stereotactic examination in which the breast is irradiated from two different angles. The irradiation unit is swiveled out of the resting position by ±10° or by ±15° about the horizontal axis with a fixed object table. Tomosynthesis examinations may be performed with the mammography appliance in which the irradiation unit moves continuously over a comparatively large angular range, for example, in an angular range of ±25° about the horizontal axis with a fixed object table. It is usually possible to produce an MLO (mediolateral oblique) view. During this kind of examination, the irradiation unit again moves over a large angular range, wherein the object table follows the irradiation unit so that the object table and irradiation unit are always aligned in the same position respective to each other and at the same distance from each other. The mammography appliance permits imaging of the breast to be examined in standard views, such as craniocaudal (CC) or mediolateral oblique (MLO) views.